Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
hieu vu » hieu va, hieu ve, hieu su
xuc van » duc van, vuc van, xuc ban
luc van » luoc van, luu van, duc van
anh lai » anh bai, anh tai, gianh lai
lai cua » dai cua, hai cua, lai chau
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
vu cam » vu cham, vu cao, va cam
x hoi » xa hoi, x ho, 5 hoi
o hoi » co hoi, o hoc, o hai

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach y nang ((x hoi) OR (o hoi)). hieu vu cam ((xuc van) OR (luc van)) anh lai cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc sach y nang ((x hoi) OR (o hoi)). hieu vu cam ((xuc van) or (luc van)) anh lai cua tre~".
• Adding a wildcard symbol may retrieve word variants: thuoc sach y nang ((x hoi) OR (o hoi)). hieu vu cam ((xuc van) or (luc van)) anh lai cua tre*.